Energy Analysis

Energy Efficient Homes

Experience has helped us define a cost-effective baseline for creating a higher-performance, energy efficient new home. It is natural on each project, during the planning phases, to explore the costs and benefits of upgrades to specific components about the home: glazing (high-performance windows and doors), increased insulation amounts, solar PV electric, and so forth.

Energy modelling analysis becomes very useful as a planning tool, helping to identify "low hanging fruit" - or targets of budget-obtainable opportunity - for the planned home. The chart below is one report from this analysis that is particularly helpful:

The height of the bars in this graph, indicate which house systems or components are using energy during the heating season. (Our local heating season for Smith Mountain Lake Virginia runs from October through to April.) The utility of this graph is comparing - in a relative sense - which components should be improved first to achieve greater reductions in energy use. The taller bars of "Above Grade Walls", "Windows/ Skylights", and "Slab Floors" indicate improvement opportunities to explore for cost versus benefit.

This next graph works in a similar fashion, but likely shows you a surprising result:

This is an analysis of energy consumption by component during our Smith Mountain Lake home cooling season, which usually runs from mid-May through September. You might have thought that greater attic insulation (Ceilings/ Roofs) or better Windows would make a significant difference in cooling-energy costs. Relatively, however, nothing on this chart of cooling a high-performance home compares to . . . Internal Gains.

Our electronic connected-ness, our modern conveniences of continuously-running appliances, electronics, transformers, converters, and the like come at a surprising cost - to cooling. All of these conveniences add to the internal heat loading inside your new well-insulated home during the summer. Better attic insulation, better wall insulation, and better windows are important. But clearly the low-hanging fruit to harvest in this analysis - is reduction of interior sources of 'waste' heat.

This is the kind of information you should expect and have access to, during the planning phases of your new energy efficient home design and build. It is time to build better.